Signalling clinograph



in general.

Patented Feb. l0,- 1948 UNITD s'mlms PATEN T OFFICE I SIGNALLINGCLINOGRAPH Fred M. Varney and Justin A.

Los Angeles, Calif.

Varney,

Application January 29, 1940, Serial No. 316,198v

Our invention relates to the art of ascertaining and indicatingdeviations rfrom vertical of a well borev and-is applicableto wellsurveying devices Since it is. contemplated that the present inventionwill find immediate arplication in devices that may be incorporated 'ina.

stringv o f drill pipe to serve as a deviation-wamingmeans for theconvenience of a driller, the

presentLj-disclosurewill be confined to embodiments'o'isuch character,but it is to be understoodgthat our invention is not to be restricted tov Juny narrow classof well surveying apparatus.

t `'Ilie unfavorable consequences, diillculties. and l"problemsattributable tov changes in direction in well bores are` well knownCrookedness in bore holes" results in mechanical'dilculties, includingbreaking of drill pipe, dimculties in drilling, dilculties in runningcasing, and difficulties in l'subsequent' pumping. It is not uncommonfor drill holes to deviate' so far as to enter the confines of adjacentproperties or to cause serious t damage to neighboring wells.Unfortunately, in

the` prevailing drilling practice. the hole may be v'extendedin thedirection of deviation for a considerable distance without knowledge onthe part of the driller.l If the deviation is not excessive, it maybedecided to suiler theconsequences andl to continue drilling. Ii' thedeviation is serious,

l however, it becomes necessary to draw back to the point of initialdeparture from vertical and l ing the hole for some redrill,l theprocedure -usually involving cementdistance. It is apparent,

then, that` there is a distinct and pressing need for some means todetect and evaluate any seriv. ous deviation at the very inception ofsuch deviation..

In ,ordinary ldrilling performed with proper ,care, signiilcantdeviation from the desired vertical', f 4readily ,.quat

weigh .on the vdrill or reducing the rate of drill excessive. ilexu'redrill isgencountering faulted or dipping lstrata Aor thefboundary tions..In any case if the required information ,deviation may be reduced tolignment is unusual and generally may be rrected by some simpleexpedient. Adeection may involve merely reducing the rotationor fthereplacement of an unsymmetrical bit. `li/Iorel extensive correctionprocedures may ben'ecessary where caving formations allow ofthe drillpipe or Where the between hard and soft formais availablfeto the drillerpromptly and as frequently as desired, the hole may be kept straight,and losses in drilling time attributable to bore aminimum.

In designing the particular form'of our invention here underconsideration our general object is to make known to a driller-by somesuitably simple procedure any serious substantial deviation of the borehole direction, and to do so at the drilling time.

One group' -of objects in the invention relates specifically totheproblems involved in designing such a device for operation in drillpipe. Among these objects are to achieve a rugged compact construction,to provide a structure that will not interfere -with normal circulationof-drllling fluids, to provide a self-contained apparatus requiring nocables or wires for communication with the surface, to provide anindicating apparatus adapted for relatively long periods'of continuousservice in a bore hole. and to provide a device that may be readilyinstalled in the borev hole or withdrawn therefrom without thenecessityof pulling the string of drill pille.

driller as often as he desires as to whether or not substantiallyvertical alignment is being maintained in the drilling of the bore holeand to indicate the approximate degree of any deviation, whereby thedriller may be warned to check the various drilling factors whendeviation occurs and may be informed promptly about whether or not thecorrective steps he takes sufilce to restore normal alignment of thebore hole. In other words, it is our object to meet the need for somesimple foolproof warning device or warning system to nt into routinedrilling operation without incurring the expense or involving thedisadvantages of typical well surveying instruments. We proposetoprovide what is in eilect an automatic indicating system that willperform -promptly in some simple manner without complicated vauxiliarysurface equipment and vwithout any difcult or time-consuming manip-.ulations on the part of the driller at the surface.

Our invention includes combining with a simple deviation-detector somemeans for sending a signal or series of signals up the well to indicate.whether or not' the bore hole is within a permissible range ofdeviation from vertical andto The preferred form of our invention isfurtherl vcharacterized by the concept of employing the energy of thecirculating drilling iiuid to actuate the detecting and'signailingmeans. More specifically. we have in mind employing a subterraneanmechanism in the well that has an inherent tendency to move operativelyin one direction and is adapted to be moved in the opposite oper- "ativedirection in opposition to such tendency in response to force derivedfrom the 'stream of drilling fluid. An important feature of such anarrangement is that the mechanism may be caused to reciprocate by simplyshutting ofi normal circulation of the drilling iluld to permit themechanism to operate in one direction and' then resuming the tluidcirculation to cause the mechanism to be moved in the oppositedirection. The movement of the'reciprocating mechanism produces a seriesof .signals in which the number of signals varies with the extent ofmovethe volume ofthe drilling fluid displaced by the mechanism. Anotheroblectis to provide a velocity control for the mechanism movement forvarious purposes in various forms of our invention. One such purpose isto delay the movement of the mechanism to permit the deviationdetectorto become stabilized; another purpose is to accelerate the movement ofthe mechanism between signal points; and a third purpose is toaccelerate the rate of pressure rise in the drilling iiuid when pressurechanges in the drilling uid are employed for signals. l

In one form -of our invention the deviationdetector is in the form of apendulum and we have the further object of automatically locking thependulum at a gravitational position prior to arrest of the mechanismmovement by the pendulum. A still further object relating to such apendulum is to provide for automatically constraining or immobilizingthe pendulum during normal drilling to avoid damage to the pendulum bythe vibration and shock incidental to drillin'g.

The above and other objects and advantages of our invention will beapparent from the following detailed description taken with the acstemsub incorporating the preferred form of our invention;

Fig. 2 is a similar view to indicate how a certain reversal of parts maybe made in modifying the structure of Fig. i:

Fig. 3 is a fragmentary view ofthe same char- Fig. 4 is a similar viewto suggest how the dashpot arrangement in Fig. 1 may be altered forcertain desirable dashpot effects:

Fig. 5 is an axial section through a special drill stem subincorporating a. second form of our invention: v

Fig. 6 is a similar view showing a third for of the invention;

Fig. 7 is a fragmentary view of the same character to indicate how aportion of the structure 4shown in Fig. 6 may be modiiied; and

Fig. 8 is a fragmentary axial section similar -to Fig. 5 to indicate howthe upper structure in Fig. 5 may be modied to provide a structure inwhich sound signals are transmitted through vthe metal of the drillstring.

Our invention may be enclosed in a, special drill collar or sub in thedrill string oi .a well immediately above the bit. In the particularform of our inventionshown in Fig. 1, such a special .drill stem sub,generally designated I0.

has an enlarged upper bore I I to retain a special sleeve insert I2, anintermediate bore I3 of some- 'what less diameter to house an instrumentcase I4 of cylindrical configuration, and a lower vbore I5 leading tothe bit. The reduction in internal diameter at the lower end of theintermediate bore I3.provides a shoulder I6 to supportV a spider Ii, thepurpose of which is to seat the lower streamlined end of the instrumentcase I4 without blocking uid flow past the cylinder. Fig. 1 shows thedisposition of the various parts of the invention during normal drillingwhile the drilling iiuid is iiowing downwardly through the drill stringto the bit. A channel of adequate crosssectional dimension toaccommodate the required flow is provided not only in the sleeve insertI2, but also around the instrument case I4.

The sleeve insert I2 has an upper bore 20 corresponding to the normalbore of a drill collar. Below the upper bore 20 the sleeve is-enlargedin internal diameter, but is provided with a series of five uniformlyspaced inwardly directed annular ribs 2Ia-2Ie at which the uid channelis constricted to approximately the diameter of the upper bore 20.4

The instrument case I4 is closed at its lower end and is held in acentralized position within the sub I0 by the spider Il at the lower endof the cylinder and by centering leaf springs 22 attached to its upperend by rivets 23. The instrument case I4 provides an upper dashpotcylinder 24 and a bore 2,5 communicating with the lower end of thedashpot cylinder throughl a tapered bore 26. Below the bore 2'5 ltheinterior of the instrument case forms a pendulum chamber 21 that isenlarged in successive stages to provide ive relatively sharp annularstop shoulders28a-28e of theI same spacing as the previously mentionedconstricting ribs 2Ia-2Ie.

Slidingly mounted in the instrument case I4 is a plunger, generallydesignated 30, having an upper shank 3|, a lower shank 32, and integralcomplementary annular recess in the dashpotl acter showing an automaticdashpot valve that may be added to the structure of Fig. l:

therewith an intermediate dashpot piston 33 cooperative with the dashpotcylinder 24. The end ofthe upper shank 3| carries a plunger head 34having a spear projection 35, the head being small enough in diameter toclear the constricting ribs 2l of the sleeve insert I2 but being largeenough to choke down the stream of drilling uid to a. material extentvwhenever it registers with one of the constricting ribs. A split ring 39in a cylinder 24 serves as a stop cooperative with the dashpot piston 33to limit the upward movement .or the plunger. 'The instrument casecontains quantity-'of suitable liquid such as light oil thatis isolatedfrom the drilling duid by a suitably extensive and flexible diaphragmsleeve 31.

The lower end of thev diaphragm sleeve ,incorporates an elastic ring 38that'v tightly embraces the 4upper plunger shank 3|. and the upper endof the `diaphragm sleeve is attached `to'the surthat crowds the material'of the diaphragm'into l a complementary recess. in the cylinder wall.

While the construction provides for extension and retraction of theplunger 30 relative to the v instrument case it does not involve anychange tain the constant displacement of the combination as the plunger30 is extended upward in the operation of theinvention.

The dashpot piston `33 is provided with a dashpot passage 40 thatpreferably is reduced in diameter at one end to provide a'sharp-edgedorifice 42,'the purpose oi the sharp-edged orifice being to minimizevariations in the rate of dashpot ilow that might result from changes inviscosity of the dashpot liquid incidental to changes in temperature.Beneath the piston 33 and acting between the piston and the bottom ofthedashpot cylinder 241s ahelical lift spring 43 that continuously urgesthe plunger 30 upward into4 extended disposition. The spring is not ofpressure against the plunger head 34 so that during normaldownward flowof the drilling fluid the plunger is in` the retracted' dispositionindicated in Fig. 1. l

Attached to the end of the lower plunger shank 32 4by a pin 44 is asocket or bearing 45 for a ball ried downward by the retraction of theplunger 30. The upper surface or rear oi the pendulum A head, however.is flat or concave to favor engagement of the head with one oi theannular stop shoulders 28 when the pendulum is inclined during an upwardor extension movement-of the' plunger. The operation of the arrangementof our iny vention shown in Fig.v 1 may be readily understood from theforegoing description. During normal drillingoperation the dynamicpressure of the downwardly owing drilling mud against the L plunger head34 keeps the plunger 30 in retracted disposition in opposition to thelift spring 43.

To make a test for bore-hole deviation the driller stops rotation of thedrill string. and then stops 4the mud pumps. As soon as the drillerstops themud pumps, thereby cutting oi circulation oi' the drillingfluid, the spring 43 becomes effective to lift the4 plunger 30 towardits fully extended position. If the plunger 38 is permitted to moveupward to the limit determined by the stop ring 33, the plunger head 34will reach the enlarged space above the uppermost constricting rib 8in.

A`rounding dashpot cylinder 24 by a split ring 384 The upward movementof the plunger must be smooth and relatively slow vto permit thependulum 41 to' become stable at its natural gravitational position andto prevent the pendulum from being deflected by resistance of the iiuidin which it is immersed. The upward movement of the plunger 30 isretarded to the required slow rate, because the ui'd in the instrumentcase above the piston 33 must bedlsplaced through the'dashpot passage40.

-The upward movement of the plungerextends `to the maximum levelpermitted by the stop ring 39 only if the drill stem su'b I 0 issubstantially vertical so that the pendulum takes a gravitationalposition coaxial with the sub and therefore'escapes even the uppermost,small-diameter stop shoulder 28a.- Ii', however, the drill stem sub I0is inclined away from the vertical, the pendulum head 48 will engage oneof the annular stop shoulders 28.

If the. deviation from vertical exceeds 4, the pendulum will becomestabilized at the corre sponding inclination relative to the sub axis inthe interval of a minute or more in which the sufllcient strength towithstand normal dynamic pendulum head approaches the level of thelowermost annular stop shoulder 23e and the pendulum head will thenengage the annular stop shoulder 28e to arrest the upward movement ofthe plunger 3D. At this arrested position of the plunger heady 34- thelower circumferential edge of the plunger head will be at approximatelythe level indicated by the dotted line E. If the deviation is Abetween 3and 4, the pendulum head 48 will clear the annular stop 'shoulder 23e,but will engage the next annular stop shoulder 28d. .In like manner adeviation from vertical of between 2 and 3 will cause the pendulum to bestopped bythe annular stop shoulder 28e; -a deviation o! 1 to 2 willcause the upward movement'to be arrested at the stop shoulder 28h;

, and if the deviation is between !/2 and 1 the uppermost annular stopshoulder 28a will be effective. Dotted lines A, B, C, and D representrespectively arrested positions of the plunger head'34 when the pendulumhead 48 engages respectivelyv the annular stop shoulders 28a, 28h,

28e, and 28d.- vIt is apparent that if no stop shoulder is engaged theplunged will rise to its fully extended position with the plunger headabove the uppermost constricting rib 2i.

After stopping the mud pumps, the driller waits for an interval ofsufcient duration to permit the plunger 30 to cover its maximum range oflongitudinal movement. The driller then starts the mud pumps to resumethe downward iiow of drilling iluidfwhich downward now exerts dynamicpressure against the plunger head and causes the plunger to retracttoward its lowermost position. As the plunger 30 retracts at a ratelimited by the described dashpot action, the plunger head 34 movesslowly past whatever `constricting,ribs 2| lie between its position ofarrest and its normal retracted position. It the drill stem sub l0 isclose enough to vertical to permit maximum upward extension of theplunger 30 the plunger head 34 on its downward movement will .approachand' pass the five constricting ribs 2| in succession, thereby causingthe downowing drilling stream to be retarded and released live times atsubstantially uniformly spaced time intervals. Even if the temporaryreductions in the rate of flow of the drilling uid are relatively mild,they may be readily detected by pressure-responsive means at the top ofthe well. In our preferred practice. however,

the reductions in flow caused by the plunger head cooperating with theconstrlcting ribs are relativelyi severe, s severe as to cause adistinctly discernible water-hammer wave to traverse the column ofdrilling fluid to the surface of the well.

It is apparent that a series of ve signals will indicate that the wellbore is within the tolerance oi' Af from vertical; four signals willindicate an inclination of V2" to'1 from vertical; three signals willindicate a deviation of between 1 and 2 from vertical; two signals willindicate a deviation of 2 to 3; one signal will indicate a deviation of3 to 4; and if no signals are received the driller will be informed thatthe deviation is greater than 4.

The purpose of Fig. 2 is to suggest a certain reversal of parts that maybe made in the portion of Fig. 1 that periodically restricts the ilow ofthe drilling fluid as the plunger 3U moves downward toward its normalretracted position. Fig. 2 shows a special drill stem sub 50corresponding to the special sub l of Fig. 1. I'he special sub 58 has asleeve insert 52 that corresponds to the sleeve insert I2, but providesonly one constriction 53 instead of the ilve constrlcting ribs ofFig. 1. The rest of the arrangement is identical with the arrangement ofFig. 1, corresponding numbers indicating corresponding parts, except theplunger head 55 which comprises in effect five individual head elements.56 in one integral structure providing alternate reduced and enlargeddiameters. 'Ihe spacing of the head elements 56 longitudinally of theplunger 30 is the same as the spacing of the constrlcting ribs2l of Fig.1 so that as the plunger head 55 descends, it cooperates with the sleeveinsert 52 to throttle the ow of the drilling fluid in the same manner asachieved by the arrangement in Fig. 1.

Fig. 3 suggests the addition to Fig. 1 of a valve member 58 in the formof a collar slidingly mounted on the lower plunger shank 32 to close thedashpot passage 40 at least partially whenever relatively high mudpressure on the plunger head 34 at a now-constrlcting position of theplunger head tends to accelerate the downward 'movement of the plunger38. The collar rests on the upper end of the previously mentioned liftspring 43 and is normally maintainedata position slightly spaced belowthe piston 33 by a second spring 59 that is somewhat stronger than therst spring 43. The spring 59 rests upon the valve member 58 and embracesa downward extension 68 of -a dashpot piston 6 I. Except for 'thesubstitution of the piston 6 I' for the piston 33 and the addition ofthe valve member 58 and the second spring 59, the arrangement suggestedby Fig. 3 is identical with' the arrangement shown in Fig. 1.

The valve memberV 58 in Fig. 3 is normally held in spaced relation tothe piston and does not interfere withthe operation of the plunger.

sure rise at each of the constrictingpositions of Whenever a rise inpressure at a flow-constrlcting position of the plunger head causes thepiston 6I to accelerate sharply the piston moves against the valvemember 58 because the valve member is retarded both by its own inertiaand by its own effect in restricting ilow past its periphery. The valvemember 58 closes or partially closes the lower end of a dashpot passage62 in the piston 6I that corresponds to the dashpot passage 40 in thepiston 33. As a result of this arrangement the dashpot passage 62 isautomatically throttled whenever relatively high pressure builds upsufcient to tend to accelerate sharply the downward movement of theplunger 30. The virtue of such the plunger head.

Another manner in which the arrangement of Fig. 1 may be modified toaccentuate lthe pressure signals by automatically controlling themovement of the plunger 36 may be understood by referring to Fig. 4.This particular modification involves substituting a new piston assemblyfor the piston 33 of Fig. 1- and involves the provision of by-passingrecesses in the wall ofthe instrument case, but in all other respectsthe arrangement of Fig. 4 is identioalwith the arrangement Y' of Fig. 1,as indicated by the use of correspond- Ving numerals for correspondingparts.

Fig. 4 shows a piston 65 corresponding to the piston 33 of Fig. l andmounted in a dashpot cylinder 24a corresponding to the dashpot cylinder24. The piston 65 has a lower extension 66 of reduced diameter' thatterminates in a sharp edged annular flange 61 that is sufllciently closeto the internal diameter ofthe cylinder 24a to have a marked dashpoteffect. The usual lift spring 43 in the bottom of the cylinder 24apresses upward against the lower face of the piston 65 be# low theflange 61. The piston 65 is provided with an inclined dashpot passage 68corresponding to the dashpot passage 40 of Fig. 1. The dashpot passage68 is `of uniform internal diameter and is controlled at its upper endby a valve member 69 in the forml of a suitable ring that slidinglyembraces the upper plunger shank 3| and rests on the upper face of thepiston 65. The valve member 69 is normally held against the upper faceof the piston by a suitable valve spring l0 embracing the-upper shank 3I the spring being conned between the valve member 69 and a collar 1Ithat is anchored on the upper shank by a suitable pin 12,. The valvemember 69 is provided with a relatively small fluid passage 14 that isrestricted at its upper end to form a. sharp-edged oriue 15. It iscontemplated that the nuid passage 14 in the valve member 69 will becontinuously in communication with the larger capacity dashpot passage68, and to insure such communication when the smaller passage is out ofregistry with the larger passage we provide an inter-V mediary annulargroove 'I6 in the upper face of the piston 65 in communication with boththe small passage 14 and the larger passage 68.

The dashpot cylinder 24a has a number of bypass recesses l1 in its innercylindrical wall spaced within the range of movement of the dashpotiange 61. In the preferred form of our invention these by-pass recessesTI are suitab...4 dimensioned annular grooves in the wall o! thecylinder 24a, but other forms of recesses may be provided. The by-passrecesses 11 are spaced in accord with the spacing of the constrlctingribs 2i in the sleeve insert I2.

When the mud pumps are started up after the piston 65 has completed itsupward movement,

the spring 'l0 maintains the valve member 68 in its lowermost positionuntil the pressure created by the mud pump in the mud column rises to a`substantial extent and the spring thereby initially retards thedownward movement of the piston 65 until the velocityof the mud streamis high enough for an eiective lnrst signal wave.

manner of a check valve rate Aat which the llcng attached to the dashpotcylinder by pendulum support' menaces The upward movement of the piston08 is controlled both "by the dashpot enect of -the small passage 14 inthe'valve-member 88.-the valve ing eiiect'is less but the piston is notmaterially accelerated at such times because the dashpot e'ect or thesmall passage 14 islstill effective. On the downward movement of thepiston 88,

eilect. of the 4piston flange .81. As'

'|08 provides nuidcommunloation between the interlor'of theinner'cyllnder |01 and the interior howeverfthevalve member 88 is liftedinthe to permit relatively free now through the dashpot passage 68, andthe primarily by the clearance for iluid ilow around piston descends iscontrolled valve member 88 rises to clear the dashpot passage 88, thepiston 85 moves downward ata moderaterate until the piston flange 81reaches a by-pass recess 11. The by-pass recess 11 provides such ampleclearance for iiuid ilow past the' 81 that the piston spurts in itspiston flange downward movement for a distance corresponding vto thevertical dimension ofthe by-pass recess. a downward spurt in themovement of the piston 68 occurs shortly before the plunger head. ofFig. 4l reaches one of the constricting ribs 2|, the plunger headslowing down abruptly at the end of the spurt as the plunger headreaches or' approaches vregistration with the lconstrictiiig rib. The-result ofyarying the velocity of the downward movement of the piston inthe manner described is to increase the intensity of the waterhammerAshock and to steepen the front of the indicating pressure wave thatIpasses upward through the mud column.

Another form of our invention shown ln Fig. 54 is housed in la specialldrill stem sub 80 that is like the drill vstemsub I and in like manneris equipped witha sleeve insert 8| having a series of annulartiow-constricting ribs 82. .An instru- .ment case 83 is supported in thesub 80 by a spider-84 and is maintained in a centralized position b'yleat'springs 88 at its upper'end.

The upper portion of the instrument case comprises a dashpot cylinder 88that embraces a hollow plunger 81 `and a slidable sleeve .88 in the-pathof the plunger. The hollow plunger 81 is integral with a piston 80 andthe piston 90 is in turn integral with` an upwardly extending plungershank 8| that terminates' in a plunger head 82. 1 The'piston 90 has adashpot' passage 83 thatlterminates in a central recess 94 and theinterior` of the hollow plunger 81 has a. conical en'd wall 30 leadingto the central'recess. To isolate the dashpot uid a diaphragm sleeve 98is connected by an elastic ring 81 at one end to the plunger shank 9|and is connected at the other end to the dashpot cylinder 88 by a splitring 88 engaging a xed ring 99, the ilxed rivets The lower interior endof the instrument case 83 provides a recess |02 in which the reducedlower end 08 of a pendulum support |04 is seated and is anchor thereinbya cross pin |05. The |04has a head or ilange |08 to Jwhich an innercylinder |01 is fixed by pins |08. 'I'he inner cylinder- |01 isslidingly embraced by the' previously mentioned slidable sleeve 88 andis integral at its upper end with a. bearing block |08 that provides asocket ior a ball member llt.

The by-pass recesses are so located thatring ofthe dashpot cylinder 88above the hearing block.

atively slight inclination from the vertical on the part of the stop-armH3 the hollow plunger 81 on downward movement will clear all'oi the stopilanges except the lowermost flange: at somewhat greater inclination ofthe stop-arm the hollow plunger will labut the next to lowest stopflange; and at maximum inclination -indicated by the arrangement the topend H6 of the stoparm will block the downward movement of the hollowplunger. The inclination of the stop-arm ||3 is controlled by adownwardly extending pendulum arm H6 having a relatively heavy pendulumweight I1 and terminating in a locking point H8.

Below the pendulum arm H8 is a locking piston |20.that is slidinglymounted in the inner 'cylinder |01 and is provided on its upper facewith a series of vconcentric locking grooves |2|.

Preferably the' lockinggrooves are dimensioned to accord with thevarious angles at which the stop-arm |3 may be eifective to arrest thedownward movement oi' the hollow plunger 81. To provide iiuid pressurefor lifting the locking piston |20 into engagement with the lockingpoint 8 of the pendulum arm we provide iluld communicationibetween the'interior of the innerA erse the series of constricting ribs82. Thelifting force of the spring I 2471s transmitted to the hollow plunger 81through an annular piston |25 embracing the pendulum support 04 andthrough the slidable sleeve 88 resting upon the annular piston. Wheneverthe hollow plunger 81 moves v downward by dynamic pressure from thedrilling A suitable vent passage in the bearing block 'u fluid, itforces the annular piston |25 downward against the resistance of thespring |24, and the downward movement ofthe annular piston displacesliquid through the bores |23 and |22 into the inner cylinder |01 to liftthe locking piston |20 against the locking point ||8.

Toobtain an indication of the bore hole alignment by means of ,theapparatus shown.. in Fig. 5, the Voperator stops the mud pumps for asufcient interval to permit the lift spring |24 to move the hollowplu'nger to its uppermost position. It will be noted that the stop-arm||3 is not eiective on the upstroke of the hollow plunger. After therequired interval of time, in which interval the pendulum becomes stableat its gravitational position, the operator starts the mud pumps and theconsequent dynamic pressure against the plunger 92 forces the hollowplunger 81 downward. On the downward movement of the hollow plunger, theplunger head 92 cooperates'wlth the constricting ribs 82 to create thepressure waves in the mud column as heretofore described. and the'number of such waves generated by the devicewill depend upon the rangeof downward movement permitted by the stop-.arm III, which range ofdownward movement, of course, depends upon the alignment oi theinstrument case 83 relative to vertical. Itis to be noted that theinitial downward movement of the hollow plunger is transmitted throughthe slidable sleeve 88 tothe annular piston |25 and therefore causes thelocking piston to immobilize the stop-arm ||3 at or near thegravitational disposition of the pendulum so that the stop-arm is rigidwhen it is met by the downwardly moving hollow plunger.

It is contemplated that the locking piston |20 will be held in its upperlocking position only so long as the annular piston is moving down wardand that when the downward movement of the annular piston ceases, thelocking piston will drop to its lowermost position to release thependulum. With this in mind we dimension the annular piston to producethe desired hydraulic eilect, but provide enough clearance for reverseleakage when stationary. Further leakage clearance is provided aroundthe locking piston |20 sleeve 88 entering the annular pendulum support|074. y

When the'hollow plunger is stopped at an intermediate position on itsdownward movement after a series of signal waves. the locking piston |20soon retreats to release thev pendulum arm ||6 and when the operatorsubsequently resumes drilling rotation, the vibration o! drilling jarsthe stop-arm ||3 free of the hollow plunger and the hollow plunger isthen driven by the dynamic pressure of the mud stream to its normalretracted position.

It is not necessary in all practices of our in,- vention to restrict orhinder to any substantial degree the downwardly flowing mud stream. Forexample, as may be understood by referring to Fig. 6, the pressure wavefor signalling borehole inclination may be generated in a by-passinterconnecting the downwardly flowing mud stream and the upwardlyflowing mud stream, the by-pass being open only during signallingperiods.

In Fig. 6 a special drill stem sub |28 has an unrestricted passage |29for carrying drilling fluid to the bit at the end of the drill string. Aby-pass |30 provided in the wall of the sub adjacent the mud passage |29has an inlet port |3| from the mud passage |29 and has an outlet port|32 for communication with vthe exterior space around the of the sub.The upper end of the by-pass 30 is provided with a suitable valve seat|33 of rubber or other material that cooperates with a valve member |34in the form of a head on the end of a plunger |36. The by-pass |30 isprovided with a. series of annular constricting ribs |30 in the samemanner and for the same purpose as heretofore described. Immediatelybelow the by-pass |30 is a dashpot cylinder |39 embracing a dashpotpiston 40 that is integral with the plunger |36. The dashpot piston |40has a pair of dashpot passages I4 that are preferably constricted attheir upper ends to form sharp-edged orices. A helical' spring |42 forcontinuously urging the plunger |36 downward is housed in the cylinder|39 in compression between1 the dashpot piston |40 and an annular flange|43 at the top of the cylinder. A diaphragm |43a is provided to seal offthe dashpot cylinder.

.Whenever the mud pumps are stopped to' interrupt vflow through thepassage I 29 pressure becomes equalized on the opposite sides of theplunger head |34 and the spring |42 has suicient force at such time tomove the plunger |36 downward to carry the plunger head to the lower endof the by-pass |30. Upon resumption of normal mud iiow, the mudstreaming through the `by-pass |30 carries the plunger head |34 upwardpast the constricting ribs |38 to the normal position against the valveseat |33, and the pressure differential between the mud passage |26 andthe exterior ofthe sub thereafter maintains the plunger head in theclosed position until the mud pumps are stopped.

4to allow for liquid displacement by the slidable The lower end |44 ofthe plunger |36 recipro-f cates in a bore |45 and carries by aball-andsocket connection a suitable pendulum |46. In the normal raisedposition of the plunger |36 the upper portion of the pendulumji46 isembraced by the bore |45 to immobilize"the pendulum. When the plunger|36 moves downward the pendulum |46 is carried into a pendulum chamber|41where it is free to seek its gravitational position. The pendulumchamber |41 is successively reduced in diameter to form a series.

of annular stop shoulders |48 that correspond in number and spacing tothe previously mentioned constricting ribs |38.

The operation Voi the arrangement shown in Fig. 6 is carried out asheretofore described by first stopping and then starting the mud pumps.Once mud circulation ceases the spring |42 moves the plunger downward ata sufllciently slow rate to permit the pendulum |46 to become stable atits gravitational position. The downward movement of the plunger |36 iscontinued to the full extent if the well bore hole is true, but isinterrupted by the pendulum |46 striking a stop shoulder |48 ii the borehole is out of vertical. When the driller starts up the mud pumps, .theplunger head |34 is carried upward past the successive constricting ribs|38, thereby generating pressure waves corresponding in number to therange of movement downward previously permitted by the pendulum |46.When the plunger |36 completes its upward movement to reach the normalposition shown in Fig. 6 both the plunger and the pendulum are lockedagainst the vibration and thrashing oi.' normal drilling.

In the arrangement shown in Fig. I a special sub |50 for the drillstring provides an unresstricted downstream passage' |5| for drilling,

mud, a radial by-pass |52 to the exterior of the sub, and a hollow wall|53 4to house a plunger control arrangement. The downstream passage |5|is enlarged to form an annular recess |54 in which is slidingly mounteda valve sleeve |65 having substantially the same internal diameter asthe passage |5|. The valve sleeve IBB-has a plurality of spaced valveports |56 positioned to register successively with the radial by-pass|52 as the valve sleeve moves upward or downward. The valve sleeve |55is connected by an arm |51 to the lupper end ot a plunger |56 that.corresponds with the plunger |36 of Fig. 6.

Fg. '7 shows the plunger |58 integral with a dashpot piston |60 in adashpot cylinder |6|', the piston having two dashpot passages |62 formedwith sharp-edged orifices. A diaphragm |62a is provided to seal off thedashpot cylinder. A

Vlift spring |63 acting between the bottom of the yi8 a pendulum chamber|41 whenever the plunger |55 moves downward.

During normal drilling operations the friction of the downwardlyiiowi'ng mud stream `on the internal walls of the valve sleeve |55 holdsthe valve sleeve at the bottom of theI annular recess .154 against theopposition ofthe lift spring |58.

assunse causes the valve sleeve |55 to move downward to bring the valveports |55 successively into registration withthe-by-pass |52. Ifthe'bore-hole alignment is close to vertical. all of the Vvalve ports|58 will -be brought into4 action to release lspurts of the drillingiiuid through the by-pass |52. Ifth'e pendulum |45 is inclined to anysignificant extent away from the axis of the drill stem sub |50'thependulum will encounter oney of a series of stop shoulders in thependulum chamber so thatthe number of times liquid is discharged throughthe by-Pass |52 will signify the alignment of the bore hole.- Theopening and closing of the by-pass |52 produces a pressure wave in themud column that may be detected at the surface of the wall.

Our `conception of a clinograph` mechanism that is moved in onedirection by yielding means and is moved in the opposite direction bypressure from the stream of drilling fluid may be incorporated in anarrangement for generating signal waves by impact of metal againstmetal, the signals being sound waves transmitted to the surface of thewell through the metal walls of the drill string. Fig. 8 shows such anembodiment of our invention.

In Fig. 8a special drill stem sub |10 provides a drilling nuid'passage|1|, the lower portion of `which is enlarged for adequate flow clearancearound an. instrument case |12. The instrument case |12 is equipped'with the usual centering springs |13. The lower portion of the'mechanism is broken away in Fig. 8 but is identical with thecorrespondingmechanism in Fig. 1. Thus the instrument case |12 rests ona spider I1 of Fig. l vand the lower portion of the instrument case hasa progressive series of sharp stop shoulders 28 adapted to be engaged bya head 48 of a pendulum 41.

i In the construction shown in Fig. 8, a dashpot piston |15 slidinglymounted in a dashpot cylinder |15 is connected to an upwardly extendingplunger shank |11 and to a downwardly extendlng plunger shank |18. Thedownwardly extending `shtml: |18 has an integral sharp-edged flange |18and terminates in a ball-and-socket mounting for the aforementionedpendulum 41. The wall of the dashpot cylinder 15 is provided 'with aseries of spaced dashpot recesses |80 for cooperation with thesharp-edged flange |18 in controlling the-rate of movement of theplunger assembly that includes the piston |15 and the two plunger shanks|11 and |18.

The piston |15 has one or more down-flow dashpot passages |52 fortransmission of the dashpot: uid when the piston moves upward 1 and hasone or more up-iiow dashpot passages |58 for service when the piston |15moves downward. An upper ring |84 slidingly keyed to the upper shank |11is adaptedto close the up-fiow dashpot passages |88 and to place arestricted orice |55 in registry with each of the downtially the sainecross-sectional areas as the upilow passage. To urge the lower' ring |80upward against the piston |15. a spring |82 lighter than the upperspring |88 is compressed between the lower ring and thev sharp-edgedange |19.

Above the series of dashpot recesses the dashpot cylinder |18 isenlarged in internal diameter to provide an annular vshoulder |88 toseat an anvil |84 in the formof a spider with radially disposed legs|85..y The anvil |84 surrounds the plunger shank |11 with liberalclearance to avoid interfering with longitudinal movement of the shank.Above the anvil |84 a tubular hammer |85 also surrounds the upperplunger shank |11. The tubular hammer |85'has an inner annular dashpotrib |81 that slidingly embraces the shank |11 and the shank 11 has anoutwardly extending annular dashpot rib |88 that is in turn slidinglyembraced by the tubular hammer. The annular space within the tubularhammer |85 between the two dashpot ribs |81 and |88 expands andcontracts with longitudinal movement of the shank relative to thetubular hammer and may be aptly termed 'an annular dashpot chamber.lNormally the tubular hammer |85 is supported in a position spacedslightly above the anvil |84 by a helical spring 20| that surrounds theshank |11 in compression between the anvil and the dashpot rib 81. It isapparent that if the plunger shank |11 moves downward at a speed thatcannot be accommodated by leakage of dashpot duid from the annulardashlpot chamber 200, the tubular hammer ,|85 will be carried downwardwith the shank' against the compression of the spring 20|, and if themovement is suiliciently rapidthe hammer will be carriedy against theanvil |84 with considerable momentum. l

The upward plunger shank 11 has a plurality of radial projections 202 tocooperate with the dashpot cylinder |15 in maintaining the alignment ofthe plunger assembly, and the shank |11 may also have an enlargedportion 203 of-4 tapered coniiguration that normally wedges into the topof the tubular hammer |85, as shown in Fig. 8, to-'hold the tubularhammer xed against vibration. A diaphragm sleeve 204 to isolate thedashpot iluid is muntedfin the previously described manner to bridge theannular space between the plunger shank 11 and the surrounding dashpotcylinder |18. The upwardly extending shank |11 terminates in astreamlined plunger head 205 that is dlmensioned to t into a normallydimensioned portion205 ofthe mud passage |1| with slight clearance, say,Je" to Fig. 8 shows the various parts of the arrangement in normaldisposition while mud is being pumped down the drilling iiuid passage|1|. at such time the pendulum 41 is immobilized in the bottom of theinstrument case, as indicated in Fig. 1, the upper ring |84 and thelower ring |80 lie against the opposite ends of the dashpot wardpressure from the tapered enlargement 203, and the plunger head 205 isin its fully retracted position in the enlarged portion of the mudpasposition, and the downward iiow of dashpot uidl through the piston islimited to the capacity of the restricted orifices |85 in the upperring. As a result of the dashpot effect the plunger assembly rises soslowly that the pendulum ,41 shown in Fig. 1 is free to become stable atits gravitational position before the pendulum head 48 reaches thelowermost annular stop shoulder 28. It is to be noted that the limitedrate of ow -permitted by the restricted orifices |85 keeps the dashpotrecesses |80 from accelerating the upward movement of the plungerassembly as the sharp-edged flange |19 passes the recesses. It isapparent that the extent of upward movement of the plunger assemblydepends upon the angle taken by the pendulum 41 and therefore varieswith the inclination of the drill stem sub |10. Since the range ofupward movement of the plunger assembly varies with the inclination ofthe mechanism, the number of dashpot recesses |80 traversed in thesubsequent downward movement of the plunger assembly will also vary withthe inclination of the sub |10.

When the operator again starts the mud pumps to resume downward flow oimud through the drill string, the pressure of the mud stream against;the plunger head 205 forces the' plunger assembly downward against theresistance of the lift spring 43. The lower ring |90 is kept closed byfluid pressure during the downward movement oi the plunger assembly, butthe upper ring |84 lifts to clear the up-ow dashpot passages |03 topermit relatively rapid ow through the dashpot passages |83. It is to benoted, however, that the spring |86 pressing downward against the upperring |84 tends to delay the downward movement of the plunger assemblyuntil the pressure of the mud stream has been built up to an eiectivevmagnitude.

Since the up-flow dashpot passages |93 are unrestricted and ofrelatively large ow capacity, the limiting factor in the rate ofdownward movement of the plunger assembly is the annular clearancearound the sharp-edged ilange |19, and the normal internal diameter ofthe dashpot cylinder |16 is so small that normally the sharpedged ange|19 causes the plunger assembly to move downwardly at a rate well withinthe leakage capacity of the annular dashpot chamber 200 so that thehammer spring 20| is permitted to hold the hammer |96 in elevatedposition, notwithstanding the downward movement of the dashpot rib |98on the plunger shank |11. Whenever the downwardly moving sharp-edgedflange |19 reaches one of the dashpot recesses |80, the annularclearance around the sharp-edged flange is increased to a flow capacitycommensurate with the flow capacity of the up-ilow dashpot passages |83and the dashpot assembly under the pressure of the downwardly flowingmud stream accelerates or spurts in its downward movement over a rangecorresponding to the vertical extent of the dashpot recess. Thearrangement is so designed that the successive spurts in the plungerassembly speed, as the sharp-edged flange passes the dashpot recesses,are above the leakage capacity of the annular dashpot chamber 200. andas a result the tubular hammer` |98 is forced sharply downward with eachacceleration of the plunger assembly and is thereby carried against theanvil |94 with such impact that a readily perceptible sound wave is sentto the surface of the well through the metal of the drill string.

Between each acceleration in the downward movement of the plungerassembly, the hammer spring 20|' is effective to restore the hammer toits normal spaced relationship to the anvil |94. It is apparent that thenumber of hammer shocks transmitted to the top of the well will indicatethe position at which the pendulum 41 stops the upward movement of theplunger assembly and will thereby indicate the current alignment of thebore hole of thewell.

In addition to sending signals to the surface v of the well in the formof sound waves transmitted through the metal oi' the drill string. thearrangement in Fig. 8 also sends signals to the surface oi' the wellinthe form of pressure waves in the columnvof circulating drilling duid.The pressure waves are created because the plunger head 205 cooperateswith the normally dimensioned portion -208 of the passage |1| to retardseverely the downwardly flowing stream of drilling iluid, but when thedownward movement of the plunger head is permitted to accelerateintermittently by temporary increased ilow through dashpot recesses |80,the downwardly flowing drill stream is likewise intermittentlyaccelerated. It is apparent, then, that either the means for creatingsound waves or the means for creating fluid pressure variations that areincorporated in the arrangement of Fig. 8 may be relied upon forindicating well-bore deviation from vertical.

In the various forms and practices of our invention exemplified by theabove described specic structures, a wide range is permissible in thedegree to which the stream of drillingiluid is restricted to create apressure variation for transmission to the surface of the well andconsiderable latitude is permissible infthe abruptness with which therestriction ofiow is accomplished. At one extreme relatively slightrestriction in ilow may be utilized for signals, the signals beingcomprehended by noting minor fluctuations in a pressure gauge incommunication with the circulating drilling iluid at the surface of thewell. At the other extreme the restriction of flow may approachcessation of ow to cause exceedingly large pressure changes in the duidstream. Again, on one hand, the pressure changes of whatever magnitudemay be so gradual as to produce no audible eiects. or, on the otherhand, may be so abrupt as to create steepfront pressure wavescharacteristic oi4 waterhammer phenomena. Such water hammerwaves may beof such amplitude as to be readily audible at the surface of the weil.

It is not dirlicult to produce a water-hammer wave of large amplitude;the velocity of the drilling huid column in a typical drill line is sohigh at acoustic velocity. In the preferred form of oui-` invention thenow-reducing means' is of such design asto retard the 4column of iiuidfor periods V of short duration. In general the duration of theretardation period is comparable to and preferably shorter than the timerequired for each water-hammer pressure wave to reach the surface of thewell. As soon as the flow-reducing means reopens after the generationofeach signal wave, the iiuid column is free to unload its accumulatedwater-hammer pressure as a spurt of fluid dawnward through the Jets inthe bit, the'unloading wave traveling with acoustic velocity up -thecolumn of uid. In the course of this unloading wave the iiuid pressurein the drill pipe drops substantially `tonormal and the pipe wallcontracts to normal dimensions.

- It is not essential that the flow-reducing means close extremelyrapidly, although if it does the water-hammer'wave front will be steepenough 4 `to produce. an audible signal shock, whereas if it closes moreslowly thev signal shock will `be subaudible. While the pressurevariations produced as described above may be severe enough to producereadily perceptible shock at the surface of thewell, in most practicesof our invention the signals will be read from some pressure-responsived'evloe such as a common pressure gauge on the in ud line.

The various forms of ourinvention described in specific detail hereinwill suggest to those skilled inthe art various changes. modifications,

and substitutions that may be made without de! parting from theunderlying principles of-the invention. and we reserve the right to allsuch changes, modifications, and substitutions that properly come withinthe scope of our appended claims.

We claim as our invention:

1. A signalling clinograph for service in a well having a channel for astream of drilling uid, said clinograph including: a mechanism forsubterranean operation in said well, said mechanism being movable inopposite` directions and being ladapted to move in one of the oppositedirections in response to said fluid stream; means cooperative' withsaid mechanism to send a series 'oi' signals to thesurface of the wellwhen saidmechanism moves;l andY a gravity-responsive deviation-detectorto limit the movement of said mechanism in accordance with the degree ofthe deviation of the well from vertical thereby to vary the number ofsignals in said series' to indicate such deviation at the surface of thewell.

2. A signalling vclinograph for service in a well having a channelfor astream of drilling fluid,

said clinograph including: a mechanism for subterranean operation insaid well. said mechanismbeing movable in opposite directions and beingadapted to move in one of the opposite directions in response to saiduid stream; means cooperative with said mechanism to send a seriesofsignals to the surface of the well when said mechanism moves; and agravity-responsive deviation-detector to limit the movement of saidmechanism in accordance with thedegree of the deviation ofthe well fromvertical thereby to vary the number of signals in said series toindlcate such deviation at the surface of the'well, said signallingclinograph as set forth being further characterized in that saidmechanism is surrounded by instrument iluid in a casing immersed in saiddrillingv fluid, said mechanism lncluding means to retard movement ofthe mechanism sufficiently to permit said gravity-responsive detector tobecome stable prior to arrival of the mechanism at a point of control,and said mechanism including a exible 4diaphragm separating saidinstrument uld from said drilling fluid, said diaphragm being adapted toyield for maintaining constant the volume of said drilling fluiddisplaced by said mechanism.

3. A signalling clinograph .for service in a well having a 4channel fora stream of drilling iiuid, said clinograph including: a mechanism forsubterranean operation in said well,V said mechanism being movable inopposite directions and being adapted to move in one of the oppositedirections in response to said fluid stream; means cooperative with saidmechanism to send a ,series of signals to the surface of the well whensaid mechanism moves; and a gravity-responsive deviation-detector tolimit the movement of said mechanism in accordance with the' degree ofthe deviation of the well from vertical thereby to vary the number ofsignals -in said series to indlcate such deviation at the surface of thewell, said signalling clinograph as set forth being furthercharacterized in that said mechanism and said cooperative means vary thefreedom of iiow of said iiuid stream repeatedly in one operating cyclethereby generating ya. series 0f pressure waves in the iiuid stream forsignals to the surface of the well.

4. A signalling clinograph for service in a well having a. channel for astream of drilling fluid, said clinograph including: a mechanism forsubterranean operation in said Well, said mechanism being movable inopposite directions and being adapted to move in one of the oppositedirections in response to said fluid stream; means cooperative with saidmechanism to send a series of signals to the surface of the well whensaid mechanism moves; and a gravity-responsive deviation-detector tolimit the movement of said mechanism in'v accordance with the degree ofthe deviation of the well from vertical thereby t0 vary the number ofsignals in said series to indlcate such deviation at the surface. of thewell, i

said signalling clinograph as set forth being fur- -ther characterizedin'that said mechanism and cooperative means make successive impacts inone operating cycle for sending sound waves to` one Operative directionand being 'adapted tol move in the opposite operative direction in re-Ispouse to said fluid stream, whereby the mechanism may be operativelyreciprocated by stopping and starting said stream: means cooperativewith said mechanism to send a series of signals to the surface of thewell when said mechanism moves; and a. gravity-responsivedeviation-detector to limit the movement of said mechanism selectivelyat various points in accordance with the amount of the deviation of thewell from vertical, thereby to vary said signals to indicate such amountof deviation at the surface of the Well.

6. A signalling clinograph for service in a well having a down channeland an up channel for circulating a stream of drillingiluid, saidclinovided with a series of spaced'constricting means within saidby-pass; means movable in said bypass `and cooperating with saidconstricting means to-vary iiow through said by-pass thereby to producepressure variations in said `stream to serve as signals to be detectedat the surface of the well; and a gravity-responsive deviationdetectorco-expensive with and adapted to control the extent of movement of saidmovable means and thereby to vary said signals in accordance with thedegree of the deviation of the well from vertical. v v

7. A signalling clinograph for service in a well having a channel for astream of drilling duid, said clinograph including: extensiie meansadapted to be immersed in said ilu-id stream at a subterranean position;yielding means continuously urging said extensiie means to extendeddisposition, said extensiie means being adapted to contract in responseto force from said stream in opposition to said yielding means, wherebysaid extensiie means may be caused to extend and contract by stoppingand starting flow of said drilling iiuid in said channel; stationarymeans in said channel cooperative with said extensiie means to vary theeiective cross section of the channel at successive stages in themovement of the extensiie means thereby to produce successive pressurevariations in the fluid at the surface of the well corresponding innumber to the range of movement of said extensiie means; andgravity-responsive means to arrest the movement of said extensiie meansat various points according tothe degree of deviation of thewell borefrom vertical, thereby to vary the number of successive pressurevariations to indicate said degrec of deviation at the surface of thewell.

8. A signalling clinograph as set forth in claim '7 in which means isprovided to control the rate of movement of said extensiie meansrelative to said stationary means in a varying manner to accentuate saidpressure variations of the fluid.

9. A signalling clinograph for service in a well having a channel for astream of drilling duid,

said clinograph including: a mechanismfor subrise caused byl 'said ymechanism-'in cooperation with said stationary means.

1l. Asignalling clinograph. as set forth in claim 9 in which said'dashpot means is 'adapted for automatic increase 'in dashpot flowto'accelerate the movement' of vsaid mechanism 4as the mechanismapproaches a position of now-restricting cooperation withsaid'stationary means, whereby the increased dashpot fiow'accelerates rapressure rise of the drilling fluid.

12. A signalling clinograph for service in a well said cllnographincluding: a'. signal means having terranean operation in said well,said mechanism having an inherent tendency to move in one operativedirection and being adapted to move in the opposite operative directionin response to ilow of said fluid stream, whereby the mechanism mayloe-operatively reciprocated by stopping and starting said stream;stationary means in said channel cooperative with said mechanism totemporarily restrict the eective cross section of the channel atsuccessive spaced points in the movement of said mechanism thereby toproduce successive pressure rises inthe nuid at the surface of the wellcorresponding in number to the range of movement of said mechanism:dashpot means to control the rate of movement of said mechanism relativeto said stationary means; and a gravityresponsive deviation-detector toarrest the movement of said mechanism at various stages according to thedegree of deviation of the well bore from vertical, thereby to vary thenumber of said successivepressn're rises to indicate said degree ofdeviation at the surface of the well.

10. A signalling clnograph as set forth in claim 9 in which the dashpotmeans includes an automatic valve to restrict the dashpot flow when arise in the iiuid pressure of said stream tends to accelerate saidmechanism whereby the automatic valve prolongs the duration of apressure dicates said degree of deviation.

a predetermined maximum signal cycle in the course of which the signalmeans" signals to the surface of the well; fluid-pressure-responsivemeans adapted to a'ctuate said signal means by energy derived from saidstream of drilling duid; and a gravity responsive deviation detectoradapted to arrestmovement'of said signal means selectively 'at spacedpoints in said signal cycle in accordance with various predetermineddegrees of deviation of the well from vertical whereby the duration ofsignal sending by the device-in- 13. A signalling clinograph for servicein a well having a channel for a 'stream of drilling fluid, saidclin'ograph including: a' signal mechanism movable through an operatingcyclto repeatedly vary 'the freedom 4of-'fiow of said iiuid thereby tosend a series of pressurevsignais through the fluid to the surface oftheweil: means to derive energy from said streamof drilling fluid toactuate said mechanism; and a gravity-responsive deviation-detectortocontrol said mechanism and modify said operating cycle to vary thenumber of pressure signals-'in said series in accordance with variouspredetermined degrees of deviation of the well from vertical.

14. A signalling clinograph for service in Va wellA having a channel fora stream of drilling fluid, said clinograph including: a reciprocatingmem'- berin said well adapted when moved'in one direction to send aplurality of successive signals to the surface of the well; a stationarymember in thewell: a pendulum mounted on one of said members; stop meanscarried by the other of said members to cooperate with said `pendulum tolimit reciprocation of said reciprocating mem,

ber at selected positions in accordance with the degree of deviation ofthe well from vertical;

yielding means to movesaid reciprocating means in one direction; andmeans responsive to said streamV to move said reciprocating means in theother direction whereby upon cessation of iiow of the drilling iiuidsaid reciprocating means moves in one direction and upon resumption .offlow movesl in the other direction and whereby the extent of movement ofthe reciprocating means and therefore the number of said signals varieswith the degree of deviation of the well from vertical.

. 15. A signalling clinograph for service in a well having a channel fora stream of drilling fluid, said clinograph including: extensiie meansadapted to be immersed in said iiuid stream; yielding means continuouslyurging said extensiie means in one direction, said extensile meansaesaesa 21 with said entensilemeans to vary the eective cross section oithe channel repeatedly in the' Vlimit the range of movement orl saidextensile means in accordance with the degree or deviation `oi.'.thewell bore from vertical, thereby to vary said pressure signals toindicate said degree of deviation.

16. A signalling clinograph for service in a well having a channel for astream of drilling a portion oi' said channel; a rst -meansreciprocative in the -well cooperative with said channelforming meanswhen moved in vone direction to alternately increase and decrease theeffective cross section of the channel repeatedly to create a series ofsign'al waves in said stream of drilling fluid, said first means beingadapted to move in one direction automatically when flow of saiddrilling uid ceases and to move in the other direction automatically inresponse to flow of the drilling fluid; a second means stationary in thewell: a gravity-responsive deviation-detector mounted on one of said rstand second means; and stop means fixed relative to the other of said rstand second means cooperative with said deviation-detector to limit atselected positions the movement of said rst means according to thedegree o! deviation of the well from vertical i whereby such deviationis indicated bythe number of signal waves in said series.

v1'?. 'A signalling clinograph for service in a well having a channelfor a stream' of drilling iluid, said clinograph including: areciprocating member in said well adapted when moved in one iiu id,'saidclinograph including: means forming dlrection'to send a plurality ofsuccessive signals to the surface of the well; a stationary member inthe well; a gravity-responsivey deviationdetector mounted on one of saidmembers; stop cooperative with said deviation-detector to limit atselected positions the movement of said reciprocating member accordingto'the degree of deviation of the well from vertical whereby suchdeviation is indicated by the number of said 'successive signals; and aretaining means responsive to movement oi said reciprocating member toimmobilize the deviation-detector automatically while saiddeviation-detector is out of the signal means signals to the surface" ofthe well; iluid-pressure-responsive means exposed to said stream foractuation of said signal means,

said duid-pressure-responsive means having a normal limit positionmaintained in response to the velocity loadof `said stream permittingilow of said stream adequate for normal drilling operation, saidiiuid-pressure-responsive means having an inherent tendency to movetowards an sure-responsive means moves towards said alternate limitposition automatically upon cessation of such flow; and agravity-responsive deviationdetector adapted to arrest movement of saidsignal means selectively. at spaced points in said s ignalf cycle inaccordance with predetermined fdesrees ot deviation-oi the well fromvertical means fixed relative to the other of said members ation andbeing adapted to move automatically towards an alternate limit positionupon cessation of such flow, said means being movable in the directionfrom said alternate position towards said normal position in response totlow of said stream and being adapted to repeatedly vary the freedom ofilow oi' the stream in the'course of such movement thereby to create aseries of pressure signals in the iluid: and a gravityresponsivedeviation-,detector to limit the movement oi" said movable means in thedirection of said alternate limit position in accordance with the degreeof deviation oi' the well from vertical thereby to vary the number ofsaid pressure signals to indicate said degree of deviation.

20. In a device of the type described tor use iia drill stem or thelike,a 4stepped member and a pendulum movable relative to each other in adirection longitudinally of said drill stem to cause engagement of saidpendulum with a portion of said stepped member depending on theinclination of said drill stem, and means for indicating at the upperend of said drill stem the portion of said stepped member engaged bysaid pendulum.

21. In a device of the character described for use in a drill stem orthe like, a member movable in said drill stem while iiuid is beingforced therethrough, cooperating flow-constricting means on said memberand within said stem, said means being relatively spaced in thedirection of movement of said member and adapted to intermittenuythrottle such flow of duid during the time said member is moving, andgravity responsive means for limiting the extent of such movement ofsaid member in accordance with the inclination vof said drill stem fromthe vertical.

22. In a device for indicating the inclination of a. drill st em or the.like, a housing adapted to be located in said drill stem, an inclinationindicating mechanism-disposed in said housing and including a. plungeradapted to Project from said v of a drill stem or the like, ahousingadapted to :alternate limit position whereby the iluid-presbe disposedin said drill stem, an inclination indicating mechanism disposed in saidhousing and dependent on variations of pressure in iiuid iiowing throughsaid drill stem for its operation, said mechanism including a plungeradapted to be projected from said housing and forming with said housingan annular opening, a lubricating and protecting fluid substantiallylling said housing for protecting` said mechanism from contact withiiuid in said drill stem, and a iiexible member connected to saidhousing and embracing said plunger to close said opening, whereby the'pressure-or said protecting and lubricating iluid mamas mersed in saiddrilling iluid in said channel, saidA housing containing a body ofiluid. for lubrication and for protection i'roin said drilling fluid: a'

mechanism mounted in said housing, including means partially in thehousing and partially immersed in said drilling iiuld and adaptedl tormovement relative to the housing in response' to starting and stoppingoi iiow oi' the drilling fluid through said channel; means cooperativewith said mechanism to send a series of signals to the surface of thewell when said mechanism moves;

a gravity-responsive deviation-detector to limit the movement of saidmechanism in accordance with the degree of deviation of the well-fromvertical, thereby to vary the number of signals in saidI series toindicate such deviation at the surface of the well; and a flexiblemember comprlsing a portion of said housing movable to compensate forldisplacement of said lubricating fluid in said housing in response torelative movel Certicate Patent No. 2,435,934.

ment oi said relatively movable means whereby the pressure oflubricating tluidin said housing and the pressure of said drilling tluidaround the housing are substantially equalized at all-times.

- .FRED M. VARNEY.

JUSTIN A. VARNEY.

l REFERENCES 'CITED The following references are 1 fue of tmspacent:

l UNITED STATES PATENTS Number Name Date 1,313,367 Anschutz-Kaempfe Aug.19, 1919 18 1,930,832 Wickershaln et al. Oct. 17, 1933 1,963,090 JakoskyJune 19, 1934 1,970,253 Smith Aug. 14, 1934 1,979,481 Lynch et al.....'NOV. 6, 1934 1,938,741 Lynch etal. Jan.'2. 1935 "20 2,046,956 Lynch.et al. July "I, 1936 2,142,559 Dulls Jam-'3, 1939 2,156,519 Walker May2, 1939 2,190,141 Walker Feb. 13, l1940 2,201,311 Halliburton May 21,1940 4 .u 4 e of Correction February 10, 1'948.

FRED M. VARNEY ET AL.

- It is hereby certified that errors appearin the printed specificationof the above I numbered patent requiring correction as follows: Column6, line 48, for the Word plunged read plunger case in the Patent Oliice.

Signed and sealed this 4th day oi May, A. D.1948.

column 19, line 10, for co-expensive. column 21, hne 64, for fload readhead; and that the said Letters read with these corrections therein thatthe same may conformto the record of the read co`-extensz`ve; Patentshould be THOMAS F. MURPHY,

Assistant Uommssoner of Patent l "of record in the n

